Polyvinyl acetal resin sheets containing benzyl hydrogen succinate



Patented Dec. 5, 1939 I v 9 I POLYVINYL ACETAL RESIN SHEETS CON- TAININGBENZYL HYDROGEN SUCCINATE Henry B. Smith, Rochester, N. Y., assignor toEastman Kodak Company, Rochester, N. Y., a corporation of New Jersey NoDrawing. Application December 15, 1937, Serial No. 180,035

2 Claims. (Cl. 260-36) This invention relates to plastic compositionsmixtures, etc., about 300 to 500 or more parts of and more particularlyto compositions comprlsthe solvent or solvent mixture being used per 100ing a polyvinyl acetal resin and a conditioning parts of the resin. Fromabout 2 to 25 parts or agent. more of dibenzyl succinate or from 2 to100 5 One object of this invention is to produce comparts or more ofbenzyl hydrogen succinate may 5 positions of matter which may be madeinto perbe employed, depending upon the nature of the manentlytransparent, strong and flexible sheets resin and the pu for which theSheets are or films of desired thinness which are substanto b used- S ip p i of the dlhenzyl tially waterproof, are unaffected by ordinary,succinate or benzyl hydrogensuccinate for any photographic fluids andpossess the desired propresin and any purpose may be readily determined10 erties of a support for sensitive photographic by experiment. For themanufacture of sheets coatings. Another object of my invention is tosuitable for photographic film base, from 2 to 25 produce compositionsof matter which can be parts of di en yl su at or of nzy d o en madeinto sheets suitable for use in laminated, succinate per 100 parts ofresin are suitable.

shatter-proof glass. Still another object is to The resin solution is.cast as a shee Solvent produce compositions which can be rolled,exevaporated, and stripped from casting surface. truded, moulded orotherwise worked into rela- Sheets for use in laminated glass may betively thick sheets and massive plastics. A furformedby casting, or maybe made without the ther object is to produce compositions suitable useof volatile solvent by extrusion, for example for use in lacquers,artificial silk filments, wrapin the manner set forth in applicationSerial No. 20

ping tissues and the like. Other objects will 147,934 of John S. Kimbleand Ernest C. Blackhereinafter appear. ard, filed June 12, 1937. Forinstance, 45 or I have discovered that a benzyl succinate sem r parts ofbe yl h en suc nate and 100 lected from the group consisting of dibenzylPa t O a P y y formaldehyde acetal resin succinate and benzyl hydrogensuccinate is a may be mixed in a suitable, jacketed mixer at a 25 usefulconditioning agent for polyvinyl acetal low tempe for example C-. d theresins. Not only do these compounds serve as mixtur m y then be w rk ono r l n e plasticizers in the accepted sense of the term, mannerdescribed in U. 8. Patent 2,048,686 of increasing the flexibility andtoughness of poly- F. R. Conklin, until complete homogenization has 0vinyl acetal resin films, sheets, or other objects taken place. The massthus produced may then or masses containing one of them, but when used ee t e ou an 31111111941 dt e tube in amounts of about 45 or more partsper 100 so formed slit to form a sheet. parts of certain of thepolyvinyl acetal resins, The P y y acetal resins can be P p y namely thepolyvinyl, acetal resins in which a reacting polyvinyl alcohol with analdehyde in predominating proportion of the acetal groups the presenceof an acetal condensation catalyst, 35 are formaldehyde acetal groups,benzyl hydrogen e. g., a mineral acid. These resins can also besuccinate hasan unusual and remarkable effect prep y simultaneouslyde-estel'ifying which I may call elasticizing That is to say, P y y p ac te d eacting the desheet of a polyvinyl formaldehyde acetal resinesterflcation product with an aldehyde in the 40 containing about partsor more of benzyl hyp esence 0! e-es y Catalyst d acetal 40 drogensuccinate per 100 parts of resin possesses condensation c y Mineralacids are a the property which, in the rubber industry, i lysts for bothde-esterfication and acetal formaknown as nerve: namely the property oftion. Among the polyvinyl acetal resins with stretching to aconsiderable extent when tension which diben zyl su c and zy hydrogen 45is exerted upon it and returning to itsoriginal succinate are useful maybe mentioned, as illus- 45 dimensions when the tension is released. Thistrative examples, the polyvinyl formaldehyde property renders suchsheets, which I shall call acetal resins, the polyvinyl acetaldehydeacetal rubbery sheets, particularly useful in the manresins, thepolyvinyl formaldehyde acetaldehyde ufacture of shatter-proof glass.mixed acetal resins, the polyvinyl butyraldehyde For the manufacture ofcast films or sheets, acetal resins and the polyvinyl buty fl 50 thepolyvinyl acetal resin and the dibenzyl sucacetaldeh-yde mixed acetalresins. cinate or benzyl hydrogen succinate may be dis- Examples of thepreparation of polyvinyl forsolved in a suitable solvent or solventmixture, maldehyde acetal resins may be found in U. S. such forinstance,as acetone, methanol, acetone- Patent 1,955,068, Examples 1, 4 and 5; inU. S methanol mixtures, ethylene chloride-menthanol Patent 2,036,092,Examples 1, 2, 3, 7 and 8; in 55 British'Patent 454,691, Examples 1, 2,3,4,5, 6

.and 7; in British Patent 404,279, Example 3;

and inBritish Patent 436,072, Examples 1, 2, 3, 4, 5, 6 and 7. Furtherexamples of the preparation of polyvinyl formaldehyde acetal resins areas follows:

ture was allowed to stand for 5 days at 40 ;C.,

after which it was diluted with acetic acid. The resin was precipitatedby pouring into cold water, washed and dried. Analysis showed the resinto have an acetate group content equivalent to 10.6% by weight ofpolyvinyl acetate and a hydroxyl group content equivalent to 7.1% byweight of polyvinyl alcohol. The stabilization} of polyvinyl acetalresins by hydroxylamine 1 is claimed in the application of Joseph B.Hale," June 23, 1937, now Patent Serial No. 149,916, filed '20 lbs. ofpolyvinyl acetate,- the viscoslty of whose molar solution in benzene was45 centidried. Analysis showed the resin tohavean acetion of harle's R.Fordyce and MarttiSalo, Serial 0 pulses, was dissolved in a mixture of336 lbs.gof

glacial acetic acid and 224 lbs. of water. After solution was effected,there were added a solutionof 318 grams of sodium nitrite in 500 cc.j'of

water, for stabilizing the resin, 15.2 lbs. of trioxymethylene and 17.5lbs; of 35% HCl. The reaction mixture was allowed to stand for 5 daysjat40 C., whereupon 5 lbs. additional 35% 'HCl' was added and the reactioncontinued for 6 days longer; a total of 11 daysat 40 C. The reactionmixture was then diluted with a mixture of acetic acid and ethylalcohol, andthe resin was precipitated by pouring into cold water,washed and tate group content equivalent to 10.7% by weight I ofpolyvinyl acetate and a hydroxyl group content equivalent to 11.2% byweight of polyvinyl alcohol. The stabilization of polyvinyl acetalresins by nitrous acid is claimed in the applica- No. 159,193, filedAugust 14, 1937, now Patent No.

Examples of the preparationof polyvinyl acetaldehyde aoetal resins maybefound in U. iS.

Patent 2,044,730, Example 1; U. s Patent 1,955,- 068, Example 2; U. S.Patent 2,036,092, Examples 4,5 and 6; British Patent 466,598,--Exampies1,5 2,"

3, 4 and 7; British Patent 404,279,-Exainples 1,; 2,

4, 5, '6, 7 and 8; U. S. Patent 1,990,399; and

French Patent 808,578, Examples '1, 2 and 3.

An additional example of the preparation of, a polyvinyl acetaldehydeacetal resin is as follows:

100 lbs. of polyvinyl acetate, the viscosity 10f whose molar solutioninbenzene was 45 centipoises, was dissolved in 300 lbs. of ethylalcohol. To this solution wereadded30 lbs. of paral dehyde and 25 "lbsof 35% HCi.v The reaction mixture wasallowed to stand for'4 days at 40C.; after which it was diluted with ethyl alcohol and the resinprecipitated by pouring into cold water, washed and dried.Analysisshowedthe resin to have anacetate groupcontentequivalent to 2.1%by weight of polyvinyl acetateand a hydroxyl group content equivalent to12.9% by weight of polyvinyl alcohol. I i

Examples of the preparation of polyvinyl formaidehyde acetaldehyde mixedacetal resins may be found in British Patent 430,136, Examples 1, 2,

3, 4, 5 and 6; British Patent 445,565, Example 2;

British Patent 465,873, Examples 1, 2, 3, 4, 5 and 6; French Patent808,586, Examples 1, 2, 3, 4, 5, 6, 12, 13, 14, 15, 16, 1'7, 18 and 19,.

Additional examples of the preparation of poly-i vinyl formaldehydeacetaldehyde mixed acetal resins are given in the application of RalphH.

Talbot, Serial No. 85,960, filed June 18, 1936, as 1 follows "Example 1parts (1.16 mol.j calculated-as monomeric vinyl acetate) ofa polyvinylacetate (45-centipoises), 100 parts of ethyl alcohol, parts of ethylacetate, 34parts. (.77 mol. as monomeric acetaldehyde) ofparacetaldehyde and 5.8 parts (.196 mol. as monomeric formaldehyde) ofpara formaldehyde were placed in an enamelled vessel and brought intosolution by stirring. When solution was complete, 10 parts of sulfuricacid '(sp. g. 1.84) in 10 parts of water were added and the mixturestirred. The mixture was maintained at a temperature of 40C. for 144-hours.

The contents of the vessel were then diluted with 5 about two and a halfvolumes of acetone, and the mixture precipitated into water. The.precipi-. tated resin waswashed free from impurities by repeated changesof cold water and dried. The

' resin, when analyzed, gave a hydroxyl group content equivalent toabout."6.4 per cent by weight of polyvinyl alcohol, an acetate groupcontent equiv, H

alent to about 4.0 percent by weight of polyvinyl acetate, aformaldehyde acetal group content equivalent to about 15.9 per cent by.weight of polyvinyl formaldehyde acetal and an acetaldehyde acetal groupcontent equivalent to about 73.9 per cent by weight of polyvinylacetaldehyde moles of polyvinyl formaldehyde acetal and about 80.3 percent by moles of polyvinyl a'cetaldehyde acetal. The resin was solublein acetone to an extent which permitted coatingfa film or sheet from theresin. V

"ma a; mol.- as monomer) "50'parts (.58 of polyvinyl acetate (45centipoises), 50 parts of ethyl alcohol, 90 parts of ethyl acetate, 17parts (.385 mol. .7 as monomer) of paracetaldehyde, 2.9 parts (.098

mol. as monomer) of parafor'maldehyde, 5 parts of sulfuric acid and 5parts of water were treated acetal. -The polyvinyl acetal portion of theresin I was therefore made up or about 19.7 per cent by as in Example 1for 161 hours; The-well washed and dried resin gave upon analysis ahydroxyl group content equivalenttoabout 9.6%by weight ofpolyvinylalcohol, an acetate group content equivalent to about 4.1% by weightofpolyvinyl acetate, Y 2. formaldehyde acetal group "content equivalent toabout 13.9 per cent by weight of p polyvinyl formaldehyde acetaL and anacetaldehyde 'acetal group content equivalent to about 69.9 per cent ofpolyvinyl acetaldehyde acetal. The polyvinyl acetalportion- Ofi'theresin was therefore made up-of about 18.5 percent by moles of polyvinylformaldehyde acetal and 81.5 per cent by moles of polyvinylacetaidehydeacetal.

Theresin was soluble in acetone. to an extent which permitted coating afilm orsheet from the resin;

Exempted 1300 parts (15.1 mol. as monomer) of a polyvinyl acetate (45centipoises) ,1700'fparts of ethyl acetate, 2250 parts of ethyl alcohol(95%) and 48 parts (1.57 mol.'as monomer) of parafo'rmaldehyde(trioxymethylene) were placed in a vessel equipped v with a refluxcondenser'and a means of agitation, and the contents brought to atemperature of about C. by means of steam heating. 182.25 parts ofsulfuric acid (sp. g. 1.84) dissolved in 51.5 parts of water were addedand the whole was heated at about 70 C. for about five hours, agitatingthroughout. At this point, 266.4 parts (6.05 mol. as monomer) ofparacetaldehyde were added and heating at about 70 C. with agitation wascontinued for a further period of twenty hours. The contents of thereaction vessel were neutralized with ammonium hydroxide and dilutedwith water precipitating the resin as a cake. The cake was cut intosmall pieces and repeatedly washed with hot water until the resin wasfree from solvents, salts and other impurities. The resin, uponanalysis, showed a hydroxyl group content equivalent to about 10.1 percent by weight of polyvinyl alcohol, an acetate group content equivalentto about 3.2 per cent by weight of polyvinyl acetate, the remainder ofthe weight of the resin being polyvinyl acetal. The polyvinyl acetalportion of the resin was made up oi. about percent by moles of polyvinylacetaldehyde acetal and about 20 percent by moles of polyvinylformaldehyde acetal. The resin was not quite soluble in acetone, butcould be made to dissolve by admixing small amounts of other solvents,such as alcohols, with the acetone.

Examples of the preparation of polyvinyl butyraldehyde acetal resinsmaybe found in U. 8. Patent 2,044,730, Examples 2, 5 and 6; BritishPatent 466,598, Example 5; Frehch Patent 813,- 303, Example 1; FrenchPatent 813,514, Examples 1, 2, 3 and 4; and British Patent 459,878,Examples 1, 2, 5, 6, 7, 8, 9 and 10.

An example of the preparation of a polyvinyl butyraldehyde acetaldehydemixed acetal resin is given in French Patent 813,303, Example 2.

What I claim as my invention and desire to be secured by Letters Patentof the United States is:

1. A transparent. rubbery sheet comprising parts of a polyvinyl acetalresin in which a predominating proportion of the acetal groups areformaldehyde acetal groups and at least 45 parts, approximately, ofbenzyl hydrogen succinate as an elasticizer therefor.

2. A transparent, rubbery sheet comprising a polyvinyl acetal resin inwhich a predominating proportion of the acetal groups are formaldehydeacetal groups, and an amount of benzyl hydrogen succinate sufllcient toimpart to the sheet a rubbery character without substantially impairingits transparency.

HENRY B. SMITH.

